<template>
  <div>
    <!--面包屑导航区域-->
    <el-breadcrumb separator-class="el-icon-arrow-right">
      <el-breadcrumb-item :to="{ path: '/' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>分类参数</el-breadcrumb-item>
    </el-breadcrumb>

    <!--卡片视图区域-->
    <el-card>
      <!--警告区域-->
      <el-alert show-icon title="注意: 只允许为第三级分类设置相关参数! "
                type="warning"
                :closable="false"></el-alert>
      <!--选择商品分类区域-->
      <el-row class="cat_opt">
        <el-col>
          <span>选择商品分类: </span>
          <!--选择商品分类的级联选择框-->
          <el-cascader expand-trigger="hover"
                       :options="cateList"
                       :props="cateProps"
                       v-model="selectedCateKeys"
                       @change="handleChanged"
                       clearable
                       change-on-select
                       ref="cascaderHandle">
          </el-cascader>
        </el-col>
      </el-row>
      <!--tab 页签区域-->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <el-tab-pane label="动态参数" name="many">
          <el-button type="primary"
                     :disabled="isBtnDisabled"
                     size="mini"
                     @click="addDialogVisible = true">
            添加参数
          </el-button>
          <!--动态参数表格-->
          <el-table :data="manyTableData" border stripe>
            <!--展开行-->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <el-tag closable
                        v-for="(item, index) in scope.row.attr_vals "
                        :key="index"
                @close="handleClosed(index,scope.row)">{{item}}</el-tag>
                <!--输入文本框-->
                <el-input class="input-new-tag"
                          v-if="scope.row.inputVisible" v-model="scope.row.inputValue"
                          ref="saveTagInput" size="small"
                          @keyup.enter.native="handleInputConfirm(scope.row)"
                          @blur="handleInputConfirm(scope.row)">

                </el-input>
                <!--添加按钮-->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">
                  + New Tag
                </el-button>
              </template>
            </el-table-column>
            <!--索引列-->
            <el-table-column type="index" label="#"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <el-tab-pane label="静态属性" name="only">
          <el-button type="primary"
                     :disabled="isBtnDisabled"
                     size="mini"
                     @click="addDialogVisible = true">
            添加属性
          </el-button>
          <!--属性参数表格-->
          <el-table :data="onlyTableData" border stripe>
            <!--展开行-->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <el-tag closable
                        v-for="(item, index) in scope.row.attr_vals "
                        :key="index"
                        @close="handleClosed(index,scope.row)">{{item}}</el-tag>
                <!--输入文本框-->
                <el-input class="input-new-tag"
                v-if="scope.row.inputVisible" v-model="scope.row.inputValue"
                ref="saveTagInput" size="small"
                @keyup.enter.native="handleInputConfirm(scope.row)"
                @blur="handleInputConfirm(scope.row)">

                </el-input>
                <!--添加按钮-->
                <el-button v-else class="button-new-tag" size="small" @click="showInput(scope.row)">
                  + New Tag
                </el-button>
              </template>
            </el-table-column>
            <!--索引列-->
            <el-table-column type="index" label="#"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit" size="mini" @click="showEditDialog(scope.row.attr_id)">编辑</el-button>
                <el-button type="danger" icon="el-icon-delete" size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>
    <!--添加参数/属性的对话框-->
    <el-dialog :title="'添加' + titleText"
               :visible.sync="addDialogVisible"
               width="50%"
               @close="addDialogClosed">
      <!--内容主体区域-->
      <el-form :model="addForm" :rules="addFormRules"
      ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <!--底部区域-->
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取消</el-button>
        <el-button type="primary" @click="addParams">确定</el-button>
      </span>
    </el-dialog>
    <!--编辑参数/属性的对话框-->
    <el-dialog :title="'修改' + titleText"
               :visible.sync="editDialogVisible"
               width="50%"
               @close="editDialogClosed">
      <!--内容主体区域-->
      <el-form :model="editForm" :rules="editFormRules"
               ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <!--底部区域-->
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取消</el-button>
        <el-button type="primary" @click="editParams">确定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
export default {
  name: "Params",
  data() {
    return {
      cateList: [],
      cateProps: {
        value: 'cat_id',
        label: 'cat_name',
        children: 'children'
      },
      // 级联选择框双向绑定数组
      selectedCateKeys: [],
      // 被激活的页签的名称
      activeName: 'many',
      manyTableData: [],
      onlyTableData: [],
      addDialogVisible: false,
      addForm: {
        attr_name: ''
      },
      addFormRules: {
        attr_name: [
          {required: true, message: '请输入参数名称', trigger: 'blur'}
        ]
      },
      editDialogVisible: false,
      editForm: {
        attr_name: '',
        attr_id: ''
      },
      editFormRules: {
        attr_name: [
          {required: true, message: '请输入参数名称', trigger: 'blur'}
        ]
      },

    }
  },
  created() {
    this.getCateList()
  },
  methods: {
    // 获取商品列表分类
    async getCateList() {
      const {data: res} = await this.$http.get('categories')
      if (res.meta.status !== 200) {
        return this.$message.error('获取商品列表数据失败! ')
      }
      this.cateList = res.data
    },
    // 级联选择框变化触发
    handleChanged() {
      this.$refs.cascaderHandle.dropDownVisible=false
      this.getParamsData()
    },
    // tab 页签点击事件的处理函数
    handleTabClick() {
      this.getParamsData()
    },
    // 获取参数的列表数据
    async getParamsData() {
      // 如果长度等于三, 表明选择的不是三级选项
      if (this.selectedCateKeys.length !== 3) {
        this.selectedCateKeys = []
        this.manyTableData = []
        this.onlyTableData = []
        return
      }
      // 证明选中的是三级分类
      // 根据所选分类的ID, 和当前所处的面板, 获取对应的参数
      const {data: res} = await this.$http.get
      (`categories/${this.cateId}/attributes`, {
        params: {sel: this.activeName}
      })

      if (res.meta.status !== 200) {
        return this.$message.error('获取参数列表失败! ')
      }

       res.data.forEach(item => {
         item.attr_vals = item.attr_vals ?
         item.attr_vals = item.attr_vals.split(' ') : []
         // 控制文本框的显示与隐藏
         item.inputVisible = false
         // 文本框中输入的值
         item.inputValue = ''
       })

       if (this.activeName === 'many') {
         this.manyTableData = res.data
       } else {
         this.onlyTableData = res.data
       }
    },
    // 监听对话框关闭事件
    addDialogClosed() {
      this.$refs.addFormRef.resetFields()
    },
    // 点击按钮, 添加参数
    addParams(){
      this.$refs.addFormRef.validate(async vaild => {
        if (!vaild) return
        const {data: res} = await this.$http.post
        (`categories/${this.cateId}/attributes`,
            {
              attr_name:this.addForm.attr_name,
              attr_sel: this.activeName
            })

        if (res.meta.status !== 201) {
          return this.$message.error('添加参数失败! ')
        }

        this.$message.success('添加参数成功! ')
        this.addDialogVisible = false
        this.getParamsData()
      })
    },
    // 编辑属性弹框
    async showEditDialog(attr_id) {
      this.editDialogVisible = true
      // 查询当前参数信息
      const {data: res} = await this.$http.get
      (`categories/${this.cateId}/attributes/${attr_id}`, {
        params: { attr_sel: this.activeName}
      })

      if (res.meta.status !== 200) {
        return this.$message.error('获取参数信息失败! ')
      }

      this.editForm = res.data
    },
    // 重置修改表单操作
    editDialogClosed() {
      this.$refs.editFormRef.resetFields()
    },
    // 点击按钮修改参数
    async editParams(){
      this.$refs.editFormRef.validate(async vaild => {
        if (!vaild) return
        const {data: res} = await this.$http.put
        (`categories/${this.cateId}/attributes/${this.editForm.attr_id}`,{
          attr_name: this.editForm.attr_name,
          attr_sel: this.activeName
        })

        if (res.meta.status !== 200) {
          return this.$message.error('属性修改失败! ')
        }

        this.$message.success('属性修改成功! ')
        this.editDialogVisible = false
        this.getParamsData()
      })
    },
    // 根据id删除对应的参数
    async removeParams(attr_id){
     const confirmResult = await this.$confirm
     ('次操作将永久删除该参数, 是否继续? ',
     '提示', {
       confirmButtonText: '确定',
       cancelButtonText: '取消',
       type: 'warning'
     }).catch(err => err)

      // 用户取消了删除操作
      if (confirmResult !== 'confirm'){
        return this.$message.info('已取消删除! ')
      }

      // 删除的业务逻辑
     const {data: res} = await this.$http.delete(`categories/${this.cateId}/attributes/${attr_id}`)

      if (res.meta.status !== 200) {
        return this.$message.error('删除参数失败! ')
      }

      this.$message.success('删除参数成功! ')
      this.getParamsData()
    },
    // 文本框失去焦点/按下Enter触发
    async handleInputConfirm(row){
      if (row.inputValue.trim().length === 0){
        row.inputValue = ''
        row.inputVisible = false
        return
      }
      // 如果没有return, 则证明输入的内容需要做后续处理
      row.attr_vals.push(row.inputValue.trim())
      row.inputValue = ''
      row.inputVisible = false

      this.saveAttrValues(row)
    },
    // 将attr_vals保存到数据库
    async saveAttrValues(row) {
      const {data: res} = await this.$http.put(`categories/${this.cateId}/attributes/${row.attr_id}`, {
        attr_name: row.attr_name,
        attr_sel: row.attr_sel,
        attr_vals: row.attr_vals.join(' ')
      })

      if (res.meta.status !== 200) {
        return this.$message.error('参数修改失败! ')
      }

      this.$message.success('参数修改成功! ')
    },
    // 点击按钮, 展示文本输入框
    showInput(row) {
      row.inputVisible = true
      // 文本框自动获取焦点
      // $nextTick: 当页面元素被重新渲染后, 才会指定回调函数中的代码
      this.$nextTick(_ => {
        this.$refs.saveTagInput.$refs.input.focus()
      })
    },
    // 删除对应的参数可选项
    handleClosed(index, row){
      row.attr_vals.splice(index, 1)
      this.saveAttrValues(row)
    }
  },
  computed: {
    // 如果按钮需要被禁用, 则返回true, 否则返回false
    isBtnDisabled() {
      if (this.selectedCateKeys.length !== 3) {
        return true
      }
      return false
    },
    // 当前选中的三级分类的id
    cateId () {
      if (this.selectedCateKeys.length === 3) {
        return this.selectedCateKeys[2]
      }
      return null
    },
    // 动态计算标题文本
    titleText() {
      if (this.activeName === 'many'){
        return '动态参数'
      }
      return '静态属性'
    }

  }
}
</script>

<style scoped lang="less">
.cat_opt{
  margin: 15px 0;
}

.el-tag {
  margin: 10px;
}

.input-new-tag {
  width: 120px;
}
</style>